Justification:
Listed as Least Concern because its extent of occurrence is greater than 20,000 km2, it can be locally abundant, and its population is not declining fast enough to qualify for listing in a threatened category.

The range of the pale kangaroo mouse encompasses the Great Basin region of west-central and south-central Nevada, extreme eastern Mono county, California, and a disjunct area in Deep Spring Valley, Inyo County, California in the United States (Hall 1946, O'Farrell and Blaustein 1974, Williams et al. 1993). It occurs mostly on fine sandy valley bottoms at elevations of about 1,200-1,750 m asl (1,530-1,590 m asl in California). The distribution comprises several disjunct geographic units.

The total adult population size is unknown but presumably exceeds 10,000. These mice sometimes are locally abundant. Hall (1946) mapped about 42 collection sites in Nevada; these likely represent at least a few dozen distinct occurrences or subpopulations. The extent of occurrence, area of occupancy, number of subpopulations, and population size probably have declined over the long term, but the degree of decline is unknown.

The species' habitat is nearly restricted to fine sands in alkali sink and desert scrub dominated by Atriplex confertifolia (shadscale) or Artemisia tridentata (big sagebrush). This mouse often burrows in areas of soft, windblown sand piled at the bases of shrubs. Pregnant individuals have been recorded from late March to mid-September. Litter size is reported to range from two to six with a mean of 3.9. This species stores and eats seeds during much of the year and takes a relatively high percentage of insects and green vegetation, especially during the breeding season. This mouse may become torpid; in spring and summer torpor is brief, employed only when starving; in winter multiday torpor may occur (French 1989). It is nocturnal; and has a burst of activity just after sundown and is active throughout the night.

Some Microdipodops populations have declined as a result of the introduction of weedy grasses and extreme habitat alteration from cultivation (e.g., irrigation of dry sinks) (Hafner et al. 1998). In addition to these human-related habitat changes, apparently natural shifts in vegetative zones have resulted in the replacement of rodent communities including Microdipodops by those including Dipodomys deserti, and vice versa (J. C. Hafner pers. obs.). Natural and human-related habitat modifications may have amplified effects on the already fragmented, patchy distribution of Microdipodops (Hafner et al. 1998).